1. Department of Anesthesiology, College of Medicine-Tucson, University of Arizona, Tucson, Arizona
2. Department of Physiology, College of Medicine-Tucson, University of Arizona, Tucson, Arizona
3. Department of Pharmacology and Toxicology, College of Pharmacy-Tucson, University of Arizona, Tucson, Arizona
4. Sarver Heart Center, College of Medicine-Tucson, University of Arizona, Tucson, Arizona